Sliding door mechanism with semi-plug features

ABSTRACT

Mechanism for driving a pair of doors through compound movement between open and closed positions wherein an inside semi-plug action is defined by moving the doors along guide tracks. An obstruction sensor may be provided in the drive linkage for recycling the door operation when an obstruction is encountered by the door.

United States Patent 1191 11] 3,844,062 Daugirdas [4 Oct. 29, 1974 I [54] SLIDING DOOR MECHANISM WITH 2,432,293 12/1947 DiGiovanni 49/28 X M G FEATURES 2,646,981 7/1953 Bassett et al v. 49/28 X 75 I K t D b d W1 In 3,453,778 7/1969 Daugirdas 49/214 1 nvnltor' mette FOREIGN PATENTS OR APPLICATIONS [73] Assgneei Cmlmamn, Chlcago, 761,447 11/1956 Great Britain...'. 49 214 [22] Filed: Nov. 30, 1972 P E K h D rimary xaminer ennet owney [21] Appl 1 310,983 Attorney, Agent, or Firm-Lloyd L. Zickert [52] US. Cl 49/28, 49/118, 49/122, ABSTRACT 49/214, 49/363 Mechanism for driving a pair of doors through com- [Sl] Int. Cl E051 15/14 pound movement between open and closed positions [58] Field of Search 49/26-28, 116418, wherein an inside semi-plug action is defined by mov- 49/122, 139, 214, 215, 363, 13 ing the doors along guide tracks. An obstruction sensor may be provided in the drive linkage for recycling [56] References Cited the door operation when an obstruction is encoun- UNITED sTATEs PATENTS tered y the door- 2,l30,764 9/1938 Conklin 49/28 X 21 Claims, 21 Drawing Figures suww v PATENTEDUET 29 I974 PATENTEDnmzs I974 Sam 7 PATENTEDncr 29 IBM 3; 844.062

sum 5 w PATENTEDum 29 m4 FIG. l5

H DOOR CLOSING MOTOR CUTOUT SENSITIVE EDGE CUTOUT (CLOSED POSITION) v DOOR OPENING CUSHION SENSITIVE EDGE CUTOUT (OPEN POSITION) DOOR OPENING MOTOR CUTOUT SENSITIVE EDGE REVERSAL SWITCH SEQUENCE TABLE SLIDING DOOR MECHANISM WITH SEMI-PLUG FEATURES This invention relates in general to a mechanism for opening and closing doors, and more particularly to a mechanism for opening and closing doors on passenger vehicles, such as rail transit cars, and still more particularly to a mechanism for effecting inside plugging of doors, and further to a door obstruction sensor for door operator mechanisms.

With the advent of modern streamlined car designs where it is desired to have doors for the ingress and egress of passengers blending into the outer walls of the car, it becomes necessary to provide a plugging action for the doors. Heretofore there have been various types of mechanisms for effecting plugging action, suchas illustrated in US. Pat. No. 3,462,881. Usually, the leading and trailing edges of a door are plugged into an opening as illustrated in the patent. Inside plugging door mechanisms already known have required a considerable amount of pocket space for receiving the doors when they are in open position.

The present invention overcomes problems heretofore encountered and provides a mechanism for controlling door movement between open and closed positions wherein a semi-plugging of the door is accomplished when it is moved nto closed position. The leading edge of the door moves directly to its closed position by being guided along a track slightly inclined with respect to the door opening. The trailing edge of the door is guided along a plugging track inorder to plug the door in the opening when it moves to closed position. The semi-plugging door mechanism of the invention can be used with single or bi-parting doors.

It is well known to provide sensing meansat the leading edges of the doors but such are subject to wear and abuse by passengers. Moreover, door edges accommodating sensitive edge mechanisms must be relatively wide and not of the interlocking type. Since a rubber nosing strip would envelop such a mechanism, it is difficult to service, and wiring connections are cumbersome.

A further feature of the invention is in a door obstruction sensor for door operator systems that is incorporated in the door operating linkage connecting the door panels to the door actuator, which enhances passenger safety. The obstruction sensor of the present invention senses door obstruction through the driving linkage, and it is therefore completely isolated from the passengers and eliminates the problems encountered in installing sensors at the leading edges of the doors. While linkage sensors have been known, such as disclosed in US. Pat. Nos. 2,578,810 and 2,646,981, where collapsible movement was incorporated with telescoping connecting rods and limited to swing type doors. the linkage sensor of the present invention is an improvement such that it can easily be used on any door operating mechanism at a pivotal joint of the mechanism, thereby also allowing for better force distribution.

The obstruction sensor of the invention includes a lost motion connection between two pivotally connected links or levers or a link and a door panel for driving a cam to actuate a switch in the event a given obstruction pressure is encountered by the door when it is moving through the closing cycle. Actuation of the switch may cause either recycling of the door to move it first to completely open position and then again through the closing cycle, or pulsation of the door.

Accordingly, it is an object of the present invention to provide a new and improved door mechanism for defining an inside semi-plug closing action on the door.

It is a further object of the present invention to provide a door mechanism for obtaining an inside semiplug closing movement wherein the leading edge of the door moves directly to closed position, while the trailing edge is plugged into closed position.

It is a further object of this invention to provide a new and improved door obstruction sensor for a door operating mechanism incorporated in the linkage connecting door panels to a door actuator which includes a lost motion arrangement associated with a pivotal joint in the linkage, and which provides better force distribution.

Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a perspective view of a vehicle including the door system of the invention to illustrate one use of the door system and in particular the door system as applied to bi-parting doors;

FIG. 2 is-an outside elevational view partially fragmentary and broken and showing some parts broken away to illustrate a part of the door supporting and driving mechanism;

FIG. 3 is a fragmentary and broken elevational view taken through the side of a vehicle having the door system according to the invention and taken substantially along line 3-3 of FIG. 2;

FIG. 4 is a fragmentary detailed plan view of the upper tracks taken generally along line 4-4 of FIG. 3;

FIG. 5 is a fragmentary detailed sectional view taken substantially along line 5-5 of FIG. 2;

FIG. 6 is a detailed sectional view somewhat fragmentary and taken substantially along line 6-6 of FIG.

FIG. 7 is a fragmentary perspective view of the lower tracks and illustrating the trailing edge of the door and showing the door in closed position;

FIG. 8 is a view similar to FIG. 7 except the door is shown in partially open position and unplugged;

FIG. 9 is a top plan view of the drive mechanism as associated with the doors and also illustrating the door and plugging tracks at the lower end of the door;

FIG. 10 is an elevational view of the door operating mechanism and taken generally along the line l0-10 of FIG. 9;

FIG. 11 is atop plan view of the door operating linkage and door in somewhat diagrammatic form and illustrating only one side of a bi-parting door arrangement wherein the parts shown in solid line represent the door and linkage in closed position, while the parts shown in phantom represent the door and linkage in open position;

FIG. 12 is an enlarged top plan view of the lost motion connection in the dividing linkage representing the obstruction sensor and showing the parts in their normal position with the sensing switchnon-actuated;

FIG. 13 is a view similar to FIG. 12 but showing parts of the joint in actuated position and showing the sensitive edge switch as being activated;

FIG. 14 is a side elevatioal view of the lost motion connection shown in FIGS. 12 and 13;

FIG. 15 is an electrical schematic diagram illustrating the components for one of the electric door operators and showing the circuit where the switch contacts are positioned as they would be when the doors are closed I and locked;

FIG. 16 is a switch sequence table representing the actuation of the limit switches utilized in the circuitry of an electric door operator;

FIG. 17 is a side elevational view of a door panel and operator arrangement where the obstruction sensor lost motion connection is mounted at the trailing edge of the door panel;

FIG. 18 is an enlarged detail view of the obstruction sensor lost motion connection shown in FIG. 17;

FIG. 19 is a top plan view of the detail shown in FIG. 18;

FIG. 20 is an electrical schematic diagram of a pneumatic door operator circuit; and

FIG. 21 is a switch sequence table for a pneumatic door operator.

The present invention relates to a sliding door mechanism for mounting and driving a sliding door between open and closed positions and where a semi-plugging effect is obtained during the closing of the door in order to have the door in flush relation to a wall structure. The door system of the invention is especially useful for passenger-carrying rail transit cars although it may be used for any type of passenger vehicle or in a stationary building. The door system of the invention embraces sliding doors and may apply to a single door for a door opening or bi-parting doors for a door opening where the doors are slidably retracted from the opening into a pocket within the vehicle wall and where the trailing edges of the doors are plugged when advanced to closed position. The door supporting mechanism principally comprises a track arrangement below the floor of the vehicle and inside the outer wall for supporting a door bar that moves within the track as well as guides the door as it moves between open and closed position. A follower connection between the door and the door bar in the track at the leading edge of the door maintains the leading edge at the same position with respect to the track throughout the travel of the door between open and closed position. The door track is arranged to be slidably inclined with respect to the door opening so that when the door is in closed position, the leading edge of the door will be flush with the door opening. and when the door is in open position. the leading edge of the door will be spaced inwardly from the door opening. The door is likewise connected to the door bar in the track at the trailing edge by means of a link which allows the trailing edge of the door to move relative to the door track. A plugging track is also provided adjacent the door track for receiving a follower directly connected to the trailing edge of the door. The plugging track serves to guide the rear edge of the door out of and into plugging relation with the door opening and along a path when the door is retracted into a pocket within the vehicle. Guide tracks of the same configuration of the door and plugging tracks are provided at the upper end of the door and associated with followers connected to the leading and trailing edges for purposes of guiding the upper end of the door in the same fashion as the lower end when the door is moved between open and closed positions.

An obstruction sensor is provided in the driving linkage for reversing or recycling the door upon sensing an obstruction at the leading edge. This sensor merely comprises a lost motion connection in a joint of the linkage which is spring biased to one position and which, upon sensing an obstruction, collapses to actuate a recycling or reversing switch to cause the door to fully open and then close or pulsate until the obstruction is cleared.

Referring now to the drawings and particularly to FIG. 1, a vehicle 20 is shown of a type to carry passengers and of a type to be driven along rails. The vehicle 20 includes side walls 21, a roof 22, a door opening 23 and bi-parting doors 24 and 25 for the door opening 23. It should be appreciated that the door system of the invention can be used with any suitable type of vehicle or in a stationary building and that the vehicle 20 illustrates one manner in which the door system can be employed for purposes of explanation in this application.

As seen particularly in FIGS. 2 and 3, the vehicle floor 26 is provided with a threshold 27 which generally weatherseals with the lower edge of the door. The leading edge 25aof the door 25 meets and abuts the leading edge 24a of the door 24 when the doors are in closed position. Further, the leading edges of the doors are substantially flush with the exterior surface of the wall 21. The trailing edges 24b and 25b of the doors'fit into the opposite vertical edges of the opening 23 and are also substantially flush with the outer surface of the vehicle 21 so that the outer surfaces of the doors essentially present a continuous surface with the outer surfaces of the wall 21 to enhance the aesthetics of the vehicle. Likewise, it will be appreciated that any number of sets of doors will be provided in one vehicle wall and also on the opposite vehicle wall if needed. By virtue of the trailing edges ofthe doors plugging into the opening 23, a tight seal and close fit and flush arrangement of the doors and exterior wall can be accomplished. It should further be appreciated that both the upper and lower edges of the doors will be flush with the upper and lower ends of the opening 23.

The mechanism for mounting the doors for sliding movement and for driving them between open and closed positions is generally illustrated in FIGS. 2 to 11 as including door and plugging tracks at both the lower and upper ends of the doors, it being appreciated that the door tracks at the lower ends of the doors generally support the weight of the doors but also guide movement of the leading edges of the doors. The plugging tracks at the lower ends of the doors guide movement of the trailing edges of the doors to effect unplugging and plugging movement of the trailing edges of the doors with the door opening. The door and plugging tracks at the upper ends of the doors merely serve to guide the upper ends of the doors during movement between open and closed positions. A single electric door operator 32 is employed for opening and closing both doors 24 and 25 although it can be appreciated that individual operators may be provided for each door if desired. It should also be appreciated the door operator could be of the pneumatic type. While the door operator in this embodiment is shown at the lower end of the door and below the floor, it should be readily recognized the door operator and associated linkage could be arranged at the upper end of the doors and in the ceiling.

The door operator 32 includes a reversible motor 23a and a gear box 32b having an output shaft 33. A double ended drive arm 34 is attached to the output shaft, one end of which is connected to linkage that is in turn drivingly connected to the door 24 and the other end of which is connected to linkage which is in turn connected to the door 25. For the door 24 a connecting link 35 is pivotally connected at one end to the driving arm 34 and at the other end to one end of a multiplying lever 36 that is pivotally mounted on a shaft 37 carried by the frame of the vehicle. The other end of the multiplying lever is pivotally connected to a connecting rod 38 which is in turn pivotally connected to the door. Also, a lost motion connection 39 is provided between the connecting rod 38 and the multiplying lever for the purpose of defining an obstruction sensor and which will be more clearly described hereinafter.

Similarly, the linkage between the door operator 32 and the door includes a connecting link 40, a multiplying lever 41 pivotally carried on a stub shaft 42 and a connecting rod 43. A lost motion connection 44 defining an obstruction sensor is arranged between the multiplying lever 41 and the connecting rod 43. When the doors are in closed position as shown in FIG. 9, the driving arm 39 relative to the pivotal connections with the connecting links and rests in an overcenter locked position whrein a stop arm 46 connected to the output shaft 33 of the operator at the lower end of the gear box 32, as seen in FIG. 10, bears against a stop 47 which presents the drive arm in overcenter locked positiori.

In the event that power is lost or the door operator malfunctions and itis desired to open the door on an emergency basis, an emergency handle 50 pivotal on a shaft 51 may be actuated to drive the arm 52, as seen in FIG. 9, against the pin 53 on the stop arm 46 to push the drive arm out of overcenter locked position so that when the doors may be opened by applying pressure against the leading edges.

Inasmuch as the door and plugging tracks for each bi-parting door are identical but merely of opposite hand, only one set of tracks will be described in detai and which will be considered the tracks for door 24. As seen particularly in FIG. 9, the lower door track for the door 24 is generally designated by the numeral 58 and extends from a point adjacent to the leading edge of the door when it is in closed position to a point deep in the door pocket 59 formed inside of the vehicle wall 21. The end of the track adjacent the leading edge of the door is closer to the outer wall than the end of the track which is deep in the door pocket. Accordingly, the door track 58 is inclined with respect to the vehicle outer wall 21. As seen in FIG. 5, the lower door track 58 is somewhat box-shaped and slidably receives therein a door slide bar divided into two parts or sections 60a and 6012 which are completely confined for movement along the longitudinal axis of the door track. The slide bar includes sections 60a and 60b inasmuch as there is a slight differential in movement between the section connected to the leading edge of the door panel and the section connected to the trailing edge thereof when the door swings between plugged and unplugged positions. Extending downwardly from the leading end of the slide bar section 60a is a pin 61, the lower end of which is pivotally connected to one end of a laterally LII extending connecting link 62, the other end of which is solidly connected to an upstanding pin 63. The upper end of pin 63 is connected to a bar 64, which is in turn connected to the lower end of the door by means of a plurality of connecting arms 65, as seen in FIG. 2. The bar 64 is parallel to the door and essentially an extension thereof and is spaced below the lower edge of the door and also below the floor 26 of the car wherein the arms 65 extend upwardly through a suitable slot formed in the floor. Inasmuch as the leading end of the bar 64 is connected essentially to the slide bar section 60a which thereby functions as a follower for the lead ing edge, the leading edge of the door will follow the slide bar section as it is moved along the door track 58.

The trailing end of the door bar 64 is connected to the slide bar section 60b by means of a swingable link 68, one end of which is pivotally connected to the door bar 64 and the other end of which is pivotally connected to a connecting link 69 extending to the slide bar section 60b as seen in FIG. 6.

The trailing end of the door bar 64 is also connected to a link 70 which has a follower 71 on the free end that is guidably received in a plugging track 72, FIG. 9. The plugging track 72 includes a straight section 72a and an arcuately shaped plugging section 7212. The straight section is essentially parallel to the door track 58, while the plugging section 72b is adjacent to the trailing edge of the door when the door is moved to closed position. By virtue of the plugging track as the door commences to move toward open position, it guides the trailing edge of the door first through an unplugging action or movement generally laterally out of door opening, and then along a substantially parallel path with respect to the door track until it reaches fully open position inside the door pocket 59. When the door moves toward closed position, the leading edge of the door is automatically driven into the openingby being guided by the door track, while the trailing edge of the door is plugged into the opening by the guiding action of the plugging track 72. It should be appreciated that the plugging track 72 does not provide any support for the door and that the door is supported entirely by the slide bar m which is guidably held in the door track 58.

The upper end of the door is merely guided by means of a door guide track 75, which is the same shape as the lower door track 58 and a plugging track 76 which is of the same shape as the lower plugging track 72. A follower 77 is connected to the leading edge of the door, while a follower 78 is connected to the trailing edge of the door. Here it can be appreciated that the follower 77 is slidably guidedin the track 75, while the follower 78 is slidably guided in the track 76, so the leading edge of the door is guided at its upper end by the door track 76, while the trailing edge of the door is guided by the trailing edge 76. It should be further appreciated that the tracks and 76 are mounted above the door open ing inside of the vehicle side wall.

It should be recognized that an obstruction sensor is desirable for a door on a public conveyance. Such a sensor may be applied to the door directly at its leading edge or it may be operable through the driving linkage for opening and closing the door. The present invention contemplates use of an obstruction sensor in the driving linkage where desired by virtue of the lost motion connections 39 and 44, FIG. 9, which are operable to sense an obstruction when the door is in the door closing cycle and thereafter reverse the door movement by conditioning the operator to go through the door opening cycle. Inasmuch as the signal to the operator is for conditioning it to go through the door closing cycle immediately upon completion of the door opening cycle caused by the obstruction sensor, the operator is automatically conditioned for a further door closing cycle. FIGS. 12, 13 and 14 specifically disclose the lost motion connection 39 associated with the linkage for the door 24, and it should be appreciated that except for having the parts of opposite hand the lost motion connection 44 will be identical.

The lost motion connection 39 representing the obstruction sensor for the door 24 includes a lost motion bar 85, one end of which is pivoted on a pin 86 carried on the multiplying lever 36. The other end of the bar 85 is pivoted to one end of the connecting rod 38 which connects to the door 24. A pin 87 extending downwardly from an intermediate point of the lost motion bar 85 and through a slot 88 formed in the end of the multiplying lever 36 whereby the pin 87 limits the relative movement of the lost motion bar 85 relative to the multiplying lever 36. As seen particularly in FIG. 14, the pin 87 extends down below the multiplying lever 36 and is connected to one end of a helical torsion spring 89. The spring is wound around the pin 86 of the multiplying lever 36 and anchored thereto against rotation, wherein a biasing force is applied to the pin 87 to cause it to normally bottom against one side of the slot 88 such as shown in FIG. 12. A switch cam 90 is secured to and rotatable with the lost motion bar 85 and engagable with a switch arm 91a of a reversing switch 91 mounted on the multiplying lever 36. During the closing cycle, should the door 24 meet an obstruction sufficient to overcome the biasing of the helical spring 89 and cause relative movement between the lost motion bar 85 and the multiplying lever 36, such as shown in FIG. 13, the cam 90 then actuates the switch 91 by depressing the arm 91a to thereby cause the reversing cycle ofthe door operator. As also seen in FIG. 13, the slot 88 will restrict the movement of the lost motion bar 85 to the multiplying lever wherein the pin 87 will bottom at the other side of the slot as seen in FIG. 13. A similar reversing switch is provided in the lost motion connection 44 of the obstruction sensor of door 25 wherein if either ofthe doors meets an obstruction, the reversing cycle will be initiated. Accordingly, the obstruction sensor feature of the invention is provided in the linkage at a pivot joint which is not susceptible to the wear or abuse it would be if at the leading edge of a door. It should be appreciated the sensor could be used with any door actuator having a pivot joint.

The operation of the electric door operator opening and closing cycles and the reversing cycle may best be understood by the electrical schematic diagram of FIG. and the switch sequence table of FIG. 16 which applies for the electric door operator only. The circuitry of FIG. 15 represents a single door operator such as the door operator 32 for doors 24 and 25. In particular, the motor 32a is represented by the field 32b and the armature 320. Direct current potential is provided to the circuit by B+ line 96 and B- line 97.

The condition of the circuit in FIG. 15 is illustrated with the switch contacts in their positions where the doors would be closed and locked. An opening signal is applied by depressing switch 100 which, while maintained in closed position, will cause the operator to go through the opening cycle and maintain the doors in open position. The closing of the switch energizes the motor control relay 101 to commence an opening cycle wherein the relay is connected across the B+ and B- lines to in turn swing motor control relay switch arms 101a and 10112 to the positions opposite to those shown in FIG. 15 and which then connects in series between the B-land B lines 96 and 97 the armature 32c and field 32b of the motor to cause the operator to drive in a direction to open the doors. When the doors are about 70 percent open, limit switch 102 is actuated by a cam 103 driven by the multiplying lever 41, FIG. 9, thereby simultaneously closing contacts 102a in the motor circuit to place in parallel with the armature an open cushion resistor 104 and thereby slow down the speed of the motor for the remainder of the opening cycle, and open the contacts 102]; to cutout the reversing cycle circuit 105, and thereby prevent actuation of the reversing cycle when the doors are fully open for when the doors reach fully open position, the lost motion connection is subjected to movement which actuates the reversing switches associated therewith. Moreover, the initial closing of the doors would cause actuation of the reversing switches. As the closing cycle begins, the door closing motor cutout switch 107 is closed to condition the operator motor circuit so that in the closing cycle it will thereafter operate to end the closing cycle at the time the doors are in fully closed position. When the doors reach their nearly fully open position, cam 103 actuates the door opening motor cutout switch 108 to open the contacts 108a in the motor circuit and thereby de-energize the motor at the conclusion of the opening cycle.

Upon opening of the control switch contacts 100, the motor control relay 101 is de-energized, thereby snapping the switch arms 101a and 101b back to the position shown in solid line in FIG. 15. Inasmuch as the door closing motor cutout switch 107 has been closed, the circuit for the motor is then conditioned so the armature 32c and the field 32b are in series across the B+ and B- lines 96 and 97 with the opposite polarity so that the motor will be driven in the opposite direction and cause the door closing cycle. At this time the closing cushion resistor 109 is automatically in parallel to the armature 32c thereby reducing the door closing speed. It will be noticed that both the open cushion resistor 104 and the closing cushion resistor 109 can be adjusted in order to adjust the cushion speed. At the end of the closing cycle, limit switch 107 will be opened and this limit switch is controlled by a cam 110 which is mounted on and rotatable with the multiplying lever 36. Also at the end of the closing cycle a limit switch 111 is actuated by a plate 112 extending from the leading edge of the door to cut out the reversing cycle switches by opening contacts 111a which would be closed during the entire closing cycle except for the very end of the cycle. This eliminates reversal of the door inasmuch as the lost motion connection is again subjected to flexing where the linkage goes solid when the door is in closed position by virtue of the fact the door is placed under sealing pressure.

In the event during the closing cycle the leading edge of either door senses an obstruction sufficient to cuase bending of the lost motion connection of one of the linkages for one of the doors, one or the other of the sensing switches including the contacts 91b and 92b are closed, and such will complete the circuit for the sensitive edge relay 102. It should be appreciated that during nearly the entire closing cycle the contacts 111a of the limit switch 111 will be closed. Moreover, the contacts 1021) representing the sensitive edge cutout for the open position will also be closed by virtue of the fact the door will be in the closing cycle. Accordingly, when one or the other of the sensitive edge switches 91 or 92 on one or the other of the lost motion connections 39 or 44 will have been actuated, a reversing cycle will take place.

Closing of the contacts 91b or 92b of the sensing switches 91 and 92 will complete the sensitive relay circuit and energize the sensitive edge relay 102 to first cause the switch arm 102a in FIG. to swing to the other contacts or line 124 to bypass the control switch 100 and cause energization of the motor control relay 101 which then in turn causes the motor control circuit to drive the motor through the opening cycle. At the same time, contacts 102b are closed to bypass the sensitive edge switch contacts 91b and 92b as'they will immediately be opened upon reversal of the cycle to hold the opening 'cycle until it has reached fully open position where it will then open normally closed contacts 125a of the sensitive edge reversal switch 125 to open the sensitive edge relay circuit and de-energize the sensitive edge relay 120, thereby causing the contacts 128 to switch back to a position shown in solid lines in FIG. 15 and de-energize the motor control relay 101 and cause the operator to proceed through a normal closing cycle. The sensitive edge relay switch 125 is also operated by the cam 41 at the same time as the door opening motor cutout switch 108 is operated.

In the event the emergency handle 50 is actuated to drive the arm 34 out of overcenter locked position so the doors can be opened, the emergency handle immediately actuates a limit switch 130 to open contacts 130a in the motor circuit and prevent energization of the motor. When the emergency handle 50 is restored to normal position, the switch contacts 130a will then be closed to normal operating procedures for the door operator can be accomplished.

In the event the crew would desire to have the doors opened without being able to actuate the control switch 100, switch arm 133 may be actuated from the exterior of the car to close the motor control relay circuit and open the door or switch arm 134 may be actuated from the inside of the car to also close the motor control relay circuit and energize the motor control relay for causing a door opening cycle.

A toggle switch 137 is provided for rendering the door operator off so the doors will not open when an opening signal is received, for testing the door operator to cause it to proceed through an opening cycle, or to allow the door operator to remain in normal condition for normal operation. As illustrated in FIG. 15, the toggle switch includes contacts 1370 in the normally closed position in the motor control circuit, contacts 13712 in the normally closed position in the sensitive edge relay circuit, and contacts 1370 in the normally closed position in the motor control relay circuit. If the toggle switch 137 is operated to swing the contacts 137a and 137C to the opposite position, testing of the door operator for the corresponding set of doors, thereby rendering the control switch inoperative.

In the motor circuit, a heat overload switch 139 is provided to protect the motor against burning out in the event a predetermined temperature is attained in the motor. Moreover, a thyrector 140 is provided in parallel with the field 32b to protect against surge currents.

Another form of obstruction sensor embodied in the linkage of an operator and in particular at a pivot joint of the linkage is shown in FIGS. 17 to 19. This arrangement differs from the arrangement of FIGS. 11 to 14 in that the obstruction sensor is here mounted at the trailing edge of the door panel. The sensor is generally desoperation of the operator to cause it to go through an opening cycle is accomplished. Release allows the closing cycle. If the toggle switch 137 is arranged in the center position between the position shown in FIG. 15 and the fully left position, it will completely turn off the ignated by the numeral at the trailing edge of a sliding door panel 151 which is opened and closed by means of a door actuator 152.

The door actuator 152 illustrated is of the electric driven type, but it may be of the pneumatic type if so desired. Moreover, the door actuator 152 is arranged in the side wall of the vehicle and generally in line with the path of the sliding door panel 151 but may be otherwise positioned in the vehicle. Specifically, the door actuator 152 includes an electric motor 153 driving a gear box 154 having an output shaft 155 on which is secured a drive arm 156. A connecting rod 157 is pivotally connected at one end to one end of the drive arm 156 and at the other end to the obstruction sensor 150.

The obstruction sensor 150 includes a mounting plate or bracket'160 that is suitably secured to the trailing edge of the door panel 151. A lost motion bar 161 is pivotally mounted at its upper end on a stub shaft carried by the mounting plate 160. A coil leaf spring 162 is also carried on the stub shaft and has one end secured to the lost motion bar 161 and the other end anchored to-a pin 163 extending from the mounting plate 160, whereby as viewed in FIG. 18, the spring exerts a continual clockwise force on the lost motion bar 161. Pivotally connected to the lower end of the lost motion bar is the connecting rod 157. The strength of the spring 162 is such that during normal closing of the door panel 151 the lost motion bar 161 will remain in the position shown in FIG. 18 substantially against a stop pin 164. In the event that an obstruction is encountered by the leading edge of the door panel 151 sufficient to counter the force of the spring 162, the spring will yield and the lost motion bar 161 will pivot in a counterclockwise direction to acutate a sensing switch 165. As seen particularly in FIG. 18, the sensing switch 165 includes an actuating arm 166 having a roller 167 on the free end, while the other end of the arm is pivotally mounted on the switch body and where the roller 167 is in position to be engaged by the lost motion bar 161 should it pivot from its rest position in a counterclockwise direction. Actuation of the switch 165 depresses a plunger 168. The switch 165 would be arranged in the control circuitry for the door actuator, such as to cause reversing of the door in the case of an electric door actuator, and pulsating of the door in the case of a pneumatic door actuator.

In order to illustrate a typical'circuit and switch sequence for a pneumatic door actuator, attention is called to the electrical schematic diagram of FIG. 20 and the switch sequence diagram of FIG. 21. Control of a pneumatic actuator is accomplished by means of a three-way magnetic valve which is illustrated in the schematic diagram of FIG. 20 by the numeral 170. The door panel is opened by depressing and holding in closed position the switch 171. Thereafter, the door is cycled through a closing movement by opening the switch 171, and during the closing cycle, in the event that an obstruction is sensed at the leading edge of the door, the lost motion bar 161 will pivot against the force of the spring 162 to actuate the sensing switch 165 closing same and thereby causing the valve 170 to again be operated for driving the door toward open position by means of closing the obstruction sensing circuit 172. As soon as the door has backed off from the obstruction sensed to allow the lost motion bar 161 to return to rest position against the stop pin 164, the valve 170 will again be conditioned to cause the actuator to move the door toward closed position. As long as the obstruction remains at the leading edge of the door, the door will accordingly pulsate. inasmuch as the spring 162 winds up so that the linkage is solid in the fully closed position of the door, a sensing circuit cutout switch 173 is actuated just ahead of full door closure to prevent the operation of the sensing switch 165. Moreover, inasmuch as initiation of the closing cycle will cause windup of the spring 162 and actuation of the sensing switch 165, a sensing circuit cutout switch 174 is provided to prevent actuation of the sensing circuit 172 until the lost motion bar has stabilized against the stop pin 164. The switch sequence table illustrating operation of the circuit is shown in FIG. 21.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims.

The invention is thereby claimed as follows:

1. In a vehicle having a door opening in the vehicle wall selectively opened and closed by at least one sliding door leaf, a mechanism for supporting the door leaf and driving same between open and closed position relative the door opening by causing the door leaf to be moved through a compound movement inwardly of the vehicle wall and laterally of the door opening to a fully open position inside the vehicle wall and along one side of the opening, said mechanism comprising upper and lower straight door tracks positioned above and below the door opening and inside the vehicle wall, means received by at least one of said door tracks for supporting said door leaf, said door tracks being at a slight incline relative the door opening so that the leading edge of the door leaf moves directly into and out ofthe closed position, follower means on the leading'edge of said door leaf slidably received in said door tracks to guide the leading edge of the door leaf, upper and lower plug tracks positioned above and below and laterally of the door opening and inside the vehicle wall, said plug tracks including a straight section inclined relative the vehicle wall and a curved section adjacent the door opening, said straight section of each plug track being substantially parallel to the adjacent door track, follower means at the trailing edge of said door leaf slidably received in said plug tracks to guide the trailing edge of the door leaf and plug the trailing edge of the door relative the door opening during movement ofthe door leaf into closed position, door actuator means, and linkage means for drivingly connecting said door actuator means to the door leaf intermediate the leading and trailing edges thereof to apply a force directly to the door leaf and drive same between open and closed positions.

2. The combination as defined in claim 1, wherein said door leaf supporting means includes a slider bar in one of said door tracks connected to the door leaf.

3. The combination as defined in claim 2, wherein the follower means at the leading edge of the door leaf of the door track receiving the slider bar is connected thereto.

4. The combination as defined in claim 3, wherein link means pivotally extends from the trailing edge of the door leaf and pivotally connects to the slider bar to provide support for the door leaf.

5. The combination as defined in claim 1, wherein said linkage means includes a connecting link, a multiplying lever pivotally mounted intermediate the ends thereof and pivotally connected at one end to said connecting link, and a connecting rod pivotally connected at one end to the other end of said multiplying lever and at the other end to said door leaf.

6. The combination as defined in claim 5, and a lost motion connection between said connecting rod and multiplying lever defining an obstruction sensor.

7. The combination as defined in claim 6, wherein said lost motion connection includes a lost motion bar pivoted at one end to the multiplying lever and pivotally connected at the other end to said connecting rod, means for limiting the relative pivotal movement between said multiplying lever and the lost motion bar and defining a biasing relation therebetween, a reversing switch on one of the lever or the bar, and means on one of the lever or the bar for actuating said switch when an obstruction is sensed by the door leaf.

8. The combination as defined in claim 6, wherein said lost motion connection includes a lost motion bar pivotally connected at one end to the multiplying lever end pivotally connected at the other end to the connecting rod, a reversing cycle switch mounted on the multiplying lever actuatable by said lost motion bar, and means for limiting the pivotal movement between the lost motion bar and the multiplying lever and for biasing the lost motion bar to a first position where the bar does not actuate the switch, whereby encountering an obstruction by the door causes movement of the bar relative the lever to actuate said switch and cause a reversing cycle.

9. The combination as defined in claim 8, wherein said means for limiting pivotal movement between the lost motion bar and the multiplying lever includes a pin extending from said lost motion bar, and a slot formed in the multiplying lever receiving said pin and having a width greater than the pin.

10. The combination as defined in claim 9, wherein said biasing means includes a spring anchored to the multiplying lever at one end and the pin at the other end.

11. The combination as defined in claim 1, further including circuit means for the actuator means controlling the opening and closing cycles of the door, wherein said linkage means includes a pivotal joint, and an obstruction sensor arranged in said linkage means at said pivotal joint, said sensor comprising a lost motion connection including a lost motion bar pivotally mounted at one end for movement between first and second positions and normally resiliently driven to said first position, and a sensing switch connected in said circuit means mounted to be actuated when said lost motion bar is forced to said second position in response to an obstruction encountered by the door.

12. In a door operator for driving a door between open and closed positions including an actuator having an output shaft, a drive arm on the output shaft, drive linkage between the drive arm and the door including a pivotal joint, and circuit means for the actuator controlling the opening and closing cycles of the door, the improvement in a door obstruction sensor arranged in said drive linkage at said pivotal joint, said sensor comprising a lost motion connection including a lost motion bar pivotally mounted at one end for movement between first and second positions and normally resiliently driven to said first position, and a sensing switch connected in said circuit means mounted to be actuated when said lost motion bar is forced to said second position in response to an obstruction encountered by the door.

13. The combination as defined in claim 12, wherein said lost motion bar is pivotally mounted to the door.

14. The combination as defined in claim 12, wherein said lost motion bar is pivotally mounted at the trailing edge of the door.

15. The combination as defined in claim 12, wherein the actuator is electrically operated, and means in the circuit means responding to the actuation of said sensing switch to condition the circuit means to drive the door in reverse through the opening cycle.

16. The combination as defined in claim 12, wherein the actuator is pneumatically operated, and means in the circuit means responding to the actuation of said sensing switch to condition the citcuit means to pulsate the door until the obstruction is cleared.

17. The combination as defined in claim 16, wherein said drive linkage includes a multiplying lever and a connecting rod and said pivotal joint is between the multiplying lever and the connecting rod, and said lost motion bar being pivotally mounted at one end to the multiplying lever and pivotally connected at the other end to the connecting rod.

18. in a door operator for driving a door between open and closed positions including a motor-reduction gear assembly having an output shaft, a drive arm on the output shaft, and drive linkage between the drive arm and the door having a multiplying lever and a connecting rod, the improvement in a lost motion connection between the multiplying lever and the connecting rod defining an obstruction sensor for the door, said lost motion connection comprising a lost motion bar pivotally connected at one end to the multiplying lever and pivotally connected at the other end to the connecting rod, a reversing cycle switch mounted on the "multiplying lever actuatable by said lost motion bar,

means for limiting the pivotal movement between the lost motion for and the multiplying leverand for biasing the lost motion bar to a first position where the bar does not actuate the switch, whereby encountering an obstruction by the door causes movement of the bar relative the lever to actuate said switch and cause a reversing cycle.

19. The combination as defined in claim 18, wherein said means for limiting pivotal movement between the lost motion bar and the multiplying lever includes a pin extending from said lost motion bar, and a slot formed in the multiplying lever receiving said pin and having a width greater than the pin.

20. The combination as defined in claim 19, wherein said biasing means includes a spring anchored to the multiplying lever at one end and the pin at the other end.

21. A sliding door mechanism for mounting a door to slide between open and closed positions relative an opening and for causing the door to have a compound motion by moving inwardly of the opening and laterally thereof, said mechanism comprising upper and lower straight door tracks positioned'above and below the opening and inward thereof, means received by at least one of said door tracks for connection to and supporting of the door, said door tracks being at a slight incline relative the door opening so that the leading edge of the door moves directly into and out of closed position, follower means in said door tracks connected to the leading edge of the door to guide same, upper and lower plug tracks positioned above, below, laterally and inward of the opening, said plug tracks including a straight section inclined relative the opening and a curved section adjacent thereto, said straight section of each plug track being substantially parallel to the adjacent door tracks, follower means in said plug tracks connected to the trailing edge of the door to guide same into and out of plugging relationship to the opening, door actuator means, and means for drivingly connecting said actuator means intermediate the leading and trailing edges of the door.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N 33 M I Dated October 29, 197 4 Inventor(s) Kristup as Daugiucdas It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, line 27, change "nto to -into--;

7 line 36, delete "the" Col. 5, line 36, change "itis to --it is--;

line no, change "when" to --then--; 001. 8, line 63, change "cuase" to --cause--; Col. 9, line 12 after "sensitive" insert --edge--; and Col. 12, line 36, change the first occurrence of "end" to --and--.

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1. In a vehicle having a door opening in the vehicle wall selectively opened and closed by at least one sliding door leaf, a mechanism for supporting the door leaf and driving same between open and closed position relative the door opening by causing the door leaf to be moved through a compound movement inwardly of the vehicle wall and laterally of the door opening to a fully open position inside the vehicle wall and along one side of the opening, said mechanism comprising upper and lower straight door tracks positioned above and below the door opening and inside the vehicle wall, means received by at least one of said door tracks for supporting said door leaf, said door tracks being at a slight incline relative the door opening so that the leading edge of the door leaf moves directly into and out of the closed position, follower means on the leading edge of said door leaf slidably received in said door tracks to guide the leading edge of the door leaf, upper and lower plug tracks positioned above and below and laterally of the door opening and inside the vehicle wall, said plug tracks including a straight section inclined relative the vehicle wall and a curved section adjacent the door opening, said straight section of each plug track being substantially parallel to the adjacent door track, follower means at the trailing edge of said door leaf slidably received in said plug tracks to guide the trailing edge of the door leaf and plug the trailing edge of the door relative the door opening during movement of the door leaf into closed position, door actuator means, and linkage means for drivingly connecting said door actuator means to the door leaf intermediate the leading and trailing edges thereof to apply a force directly to the door leaf and drive same between open and closed positions.
 2. The combination as defined in claim 1, wherein said door leaf supporting means includes a slider bar in one of said door tracks connected to the door leaf.
 3. The combination as defined in claim 2, wherein the follower meanS at the leading edge of the door leaf of the door track receiving the slider bar is connected thereto.
 4. The combination as defined in claim 3, wherein link means pivotally extends from the trailing edge of the door leaf and pivotally connects to the slider bar to provide support for the door leaf.
 5. The combination as defined in claim 1, wherein said linkage means includes a connecting link, a multiplying lever pivotally mounted intermediate the ends thereof and pivotally connected at one end to said connecting link, and a connecting rod pivotally connected at one end to the other end of said multiplying lever and at the other end to said door leaf.
 6. The combination as defined in claim 5, and a lost motion connection between said connecting rod and multiplying lever defining an obstruction sensor.
 7. The combination as defined in claim 6, wherein said lost motion connection includes a lost motion bar pivoted at one end to the multiplying lever and pivotally connected at the other end to said connecting rod, means for limiting the relative pivotal movement between said multiplying lever and the lost motion bar and defining a biasing relation therebetween, a reversing switch on one of the lever or the bar, and means on one of the lever or the bar for actuating said switch when an obstruction is sensed by the door leaf.
 8. The combination as defined in claim 6, wherein said lost motion connection includes a lost motion bar pivotally connected at one end to the multiplying lever end pivotally connected at the other end to the connecting rod, a reversing cycle switch mounted on the multiplying lever actuatable by said lost motion bar, and means for limiting the pivotal movement between the lost motion bar and the multiplying lever and for biasing the lost motion bar to a first position where the bar does not actuate the switch, whereby encountering an obstruction by the door causes movement of the bar relative the lever to actuate said switch and cause a reversing cycle.
 9. The combination as defined in claim 8, wherein said means for limiting pivotal movement between the lost motion bar and the multiplying lever includes a pin extending from said lost motion bar, and a slot formed in the multiplying lever receiving said pin and having a width greater than the pin.
 10. The combination as defined in claim 9, wherein said biasing means includes a spring anchored to the multiplying lever at one end and the pin at the other end.
 11. The combination as defined in claim 1, further including circuit means for the actuator means controlling the opening and closing cycles of the door, wherein said linkage means includes a pivotal joint, and an obstruction sensor arranged in said linkage means at said pivotal joint, said sensor comprising a lost motion connection including a lost motion bar pivotally mounted at one end for movement between first and second positions and normally resiliently driven to said first position, and a sensing switch connected in said circuit means mounted to be actuated when said lost motion bar is forced to said second position in response to an obstruction encountered by the door.
 12. In a door operator for driving a door between open and closed positions including an actuator having an output shaft, a drive arm on the output shaft, drive linkage between the drive arm and the door including a pivotal joint, and circuit means for the actuator controlling the opening and closing cycles of the door, the improvement in a door obstruction sensor arranged in said drive linkage at said pivotal joint, said sensor comprising a lost motion connection including a lost motion bar pivotally mounted at one end for movement between first and second positions and normally resiliently driven to said first position, and a sensing switch connected in said circuit means mounted to be actuated when said lost motion bar is forced to said second position in response to an obstruction encountered by the door.
 13. The combination as defined in claim 12, wherein said lost motion bar is pivotally mounted to the door.
 14. The combination as defined in claim 12, wherein said lost motion bar is pivotally mounted at the trailing edge of the door.
 15. The combination as defined in claim 12, wherein the actuator is electrically operated, and means in the circuit means responding to the actuation of said sensing switch to condition the circuit means to drive the door in reverse through the opening cycle.
 16. The combination as defined in claim 12, wherein the actuator is pneumatically operated, and means in the circuit means responding to the actuation of said sensing switch to condition the citcuit means to pulsate the door until the obstruction is cleared.
 17. The combination as defined in claim 16, wherein said drive linkage includes a multiplying lever and a connecting rod and said pivotal joint is between the multiplying lever and the connecting rod, and said lost motion bar being pivotally mounted at one end to the multiplying lever and pivotally connected at the other end to the connecting rod.
 18. In a door operator for driving a door between open and closed positions including a motor-reduction gear assembly having an output shaft, a drive arm on the output shaft, and drive linkage between the drive arm and the door having a multiplying lever and a connecting rod, the improvement in a lost motion connection between the multiplying lever and the connecting rod defining an obstruction sensor for the door, said lost motion connection comprising a lost motion bar pivotally connected at one end to the multiplying lever and pivotally connected at the other end to the connecting rod, a reversing cycle switch mounted on the multiplying lever actuatable by said lost motion bar, means for limiting the pivotal movement between the lost motion for and the multiplying lever and for biasing the lost motion bar to a first position where the bar does not actuate the switch, whereby encountering an obstruction by the door causes movement of the bar relative the lever to actuate said switch and cause a reversing cycle.
 19. The combination as defined in claim 18, wherein said means for limiting pivotal movement between the lost motion bar and the multiplying lever includes a pin extending from said lost motion bar, and a slot formed in the multiplying lever receiving said pin and having a width greater than the pin.
 20. The combination as defined in claim 19, wherein said biasing means includes a spring anchored to the multiplying lever at one end and the pin at the other end.
 21. A sliding door mechanism for mounting a door to slide between open and closed positions relative an opening and for causing the door to have a compound motion by moving inwardly of the opening and laterally thereof, said mechanism comprising upper and lower straight door tracks positioned above and below the opening and inward thereof, means received by at least one of said door tracks for connection to and supporting of the door, said door tracks being at a slight incline relative the door opening so that the leading edge of the door moves directly into and out of closed position, follower means in said door tracks connected to the leading edge of the door to guide same, upper and lower plug tracks positioned above, below, laterally and inward of the opening, said plug tracks including a straight section inclined relative the opening and a curved section adjacent thereto, said straight section of each plug track being substantially parallel to the adjacent door tracks, follower means in said plug tracks connected to the trailing edge of the door to guide same into and out of plugging relationship to the opening, door actuator means, and means for drivingly connecting said actuator means intermediate the leading and trailing edges of the door. 